There are many sections of the Tioughnioga river that make good day-trips in canoes or kayaks from Ithaca.
A nice gentle trip with just a few riffles. Suitable for beginners.
Put in at the park in Marathon. From Ithaca approach on 221, cross the river and turn immediately right onto Peck St. Park is straight ahead and there is a launching point next to a little loop in the road.
Take out under the 206 bridge (next to Hess gas station and Aeillo's restaurant). The track down to river/parking is just a few feet (literally) south of the 11/79 and 206/Main St. junction on 11/79. Google maps
With river at about 3.2ft Simeon Warner and Kata paddled this section in a little over 3 hours with a 40 minute lunch break, steady paddling but not racing. A COC beginner trip might take up to double this time (at a guess).
Minimum river level is around 3.2ft on the USGS gauge at Cortland